Epidemiologic studies on the mechanism of vertical and horizontal transmission of bovine leukemia.
D000818:Animals; D002417:Cattle; D002418:Cattle Diseases / Q000209:etiology*; D004812:Epidemiologic Methods; D007938:Leukemia / Q000453:epidemiology / Q000209:etiology / Q000662:veterinary*; D008218:Lymphocytosis / Q000453:epidemiology*